By now everyone has seen the spinning dancer illusion, and probably also the ridiculous claim that the direction the dancer turns indicates whether you're left-brained or right-brained. This version of the illusion should be enough to dissuade you of that. By looking at the left or right version of the figure, you can alternate back and forth without difficulty or effort. It's interesting to experience how our awareness snapssnapping-to is characteristic of what I mean when I say 'knowledge is recognition' - to know is to snap to awareness of the nature of some phenomenon or another.